Temperature controlled apparatus



July 4, 1933- J. A. SPENCER TEIPERATURB CONTROLLED APPARATUS Original Filed April 3, 1925 Y :31? IIIIIII a syml I Patented July 4, 1933 UNITED STATES PATENT oFmcr.

30 A. SPENCER, NEWTONVILLE, MASSACHUSETTS, ASSIGNOR TO SPENCER THEBIOSTAI. COD-ANY, 0]" CAMBRIDGE, IASSACHUSETTS, A CORPORATION OF IASSACHUSETTS rmnnarm coiwrnotnnn nrrm'rus' Driglnal application filed April 8, 1825, Serial ll'o. 80,455. Divided and this application filed December 5,

1830. Serial controlled sadiron.

This application is a division of my United States application Serial No. 20,455, filed April 3, 1925 for Temperature-controlled apparatus now Patent No. 1,812,722, dated June 30, 1931.

As disclosed in my United States Patent 1,448,240, dated March 13, 1923, the electrical heatin circuit of a sadiron may be suddenly opened when the sidiron reaches a predetermined temperature limit and automatically closed when the temperature of the iron drops to a certain predetermined lower limit. Such a control is accomplished by the use of a sna -acting thermostatic member which suddenly and abruptly changes shape at predetermined temperature limits.

Among the several objects of the present invention ma be noted the revision of a thermostatica 1y operated sa 'ron in which the temperatures at which the thermostat operates may be varied without adjusting the thermostat itself; the provision of a device of the class described in which there is provided means for regulating the temperature of the thermostatic control independent of the temperature of the sadiron itself so that the heater circuit of the iron will be automatically opened and closed at predetermined temperature limits of the iron; the provision of a device of the class described m which there is provided means for transmitting predetermined amounts of. heat to a space surroundings. thermostatic member so that said thermostatic member will automatically open and close the circuit of the heating element from which heat is transmitted; and the provision of a device of. the class described which is simple, efiective, and adapted to a wide variety of uses. Other objects will be in part obvious and in part pointed out hereinafter. a

This invention accordingly comprises the elements and combinations of elements, features of construction, and arrangements of parts which will be exem lified in the structure hereinafter descri .'and the scope of the application of which will be indicated in the fo owing claims.

In the accompanying drawing, in which is illustrated one of various possible embodi ments of the invention,

Fig. 1 is a longitudinal section of a sadiron, parts being shown in elevation;

Fi 2 is a horizontal section taken substantially upon line 2-2 of Fi .1;

Fig. 3 is an enlarged, detai edsection of the means for controllin the temperature of a thermostatic disk; and,

Fig. 4; is a view taken on line 4--4 of Fig. 3.

Similar reference characters indicate correspondin parts throughout the several views of e drawings. I

Referrin now more particularly to the drawings, t ere is represented at numeral 1 a base member having a;recess 3 formed therein, in which the thermostatic assembly indicated at 5 is located. The base member 1 is surmounted by a fiat heatin coil 7 which is connected to a terminal p ug 9 mounted upon the sheet metal shell 11. The heating coil 7 is surmounted by a weight member 13 and the several parts are retained in assembled position by bolts 15, which also hold in place a handle 17. a

As shown in Figs. 1 and 3, the recess 3 is closed by a disk 19 of insulating material which carries a stationary contacting rin 21 cooperating with a thermostatic disk 23. e thermostatic disk is mounted upon a supporting stem 25 which may be molded into the disk 19 and is held in place thereon by a nut 27 The electric heating circuit comprises a series connection of the stationary contactin ring 21, the thermostatic disk 23, stem 25 an the heating coil 7, a thin contact plate 29 connecting one terminal of the heating coil 7 to the supporting stem 25.

It will be clear from the construction shown that the temperature of the thermostatic disk normally approximates the temperature of the base member 1. The temperature of the disk may be separately controlled, however, by the provision of means for carrying predetermined amounts of heat to the space surrounding the disk. This means of transmitting a quantity of heat to the space 3 may 10o conveniently comprise a member 31 of rela tively small cross section which projects downward into the recess 3. The member 31 is provided with an arm 37 extending laterally therefrom and which is in variable heat conducting relation with a portion of the heating coil as shown in Fig. 4. If the member 31 and arm 37 are formed of metal having a relatively high thermal conductivity, heat will flow from the coil 7 through the arm 37 into the projecting end 31 by conduction and thus be transmitted to the thermostatic disk in part by radiation from the projecting end of member 31 and by conduction from the surrounding air which has been heated by the conductionof heat from .the coil 7 to this surrounding air b means of the arm 37 and the member 31, here is therefore provided a simple and effective means for conducting a heat from the heating element to the thermostat.

The member 31 is also provided with a stem portion 33 which extends upward through the weight member 13 and shell 11. A control knob 35 is aifixed to the projecting end of the stem 33. The turning of the knob 35 provides a means for varying the area of contact of the arm '37 with the heating coil 7 altering thereby the rate of transmission 0% heat to the thermostat, serving thereby to change the temperature of the thermostatic disk with respect to the surrounding base of the sadiron.

It is to be understood that the thermostatic disk 23 has substantially fixed temperature limits at which it suddenly and abruptly reverses its curvature and that the circuit of the heating coil 7 is opened when the thermostat reaches its upper temperature limit. Althou h the thermostat is in heat conducting relation to the base member 1 it is clear that the provision of a variable means for transmittmg heat tothe thermostat will cause the J thermostat to reach its operating temperature substantially before t e base member. 1 reaches a temperature equal to the operating temperature of the thermostat, and that the temperature of the base member I at which the heating circuit is opened may be varied by adjustment of the knob 35. It is therefore 0 ear that the adjustment of this knob 35 determines the u per temperature limit of the sadiron. The ow of heat is adj usted. by varying the conduction thereof through the stem 31 i The lower temperature limit of the sadiron redetermined amount of the tem rature of the sadiron and the thermostat gins to fall. When the temperature of the thermostat falls toits lower operatin temperature, the thermostat snaps to the ull-line position of Fi 3 and the circuit through the heating'coil 7 1S closed.

It is therefore clear that there is provided a means for regulatin the temperature of the sadiron without ad usting the thermostat control.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in carrying out the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing" shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. In an electrical heatin a paratus, the combination of an electrics energized heating element, a thermostat 1n heat conducting relation thereto, switching means associated with the said thermostat for controlling the said heating element, heat insulatin means between said thermostat and said heating element and manually ad'ustable means variably controlling the ra of heat conduction from said element to said thermostat, saidlast-named means comprising a rotatable member formed of heat-conducting material, and an arm on said member adapted to be brought into greater or less degree of juxtaposition with said heating element as said member is rotated.

2. In an electric sadiron which has a base member having a recess therein and a thermostat within the recess and a heating member 'uxtaposed-tosaid base member, means con ucting heat at varying rates from said heater to said thermostat com rising-a rotatable stem and an arm on sai stem ada ted to be brought into greater and less 0- grees of juxtaposition with said heater as said stem is rotated.

In testimony whereof, I have t? my name to this specification this 26 day of November, 1930.

7 JOHN A. SPENCER. 

